Compressor inlet adjustment mechanism

ABSTRACT

An adjustment mechanism variably adjusts the cross-section of a compressor inlet. The adjustment mechanism comprises a plurality of rotatable orifice elements and a transmission ring. Each orifice element has a plate body, a coupling element and a bearing pin. The transmission ring is mechanically coupled to the orifice elements via the coupling elements. One of the orifice elements is configured as a drive orifice element. The bearing pin of the drive orifice element is configured as an elongated bearing pin. The elongated bearing pin is configured longer than the bearing pins of the other orifice elements. Furthermore, the elongated bearing pin is adapted to be coupled to an actuation system such that when the drive orifice element is moved by the actuation system, movement is transmitted from the drive orifice element via the transmission ring to the other orifice elements.

TECHNICAL FIELD

This disclosure relates to an adjustment mechanism for adjusting thecross-section of a compressor inlet. Furthermore, the invention relatesto an adjustment assembly, a compressor and a charging apparatus havingsuch an adjustment mechanism.

BACKGROUND

The individual mobility sector is experiencing a disruptive change.Especially, the increasing number of electric vehicles entering themarket and stricter emission regulations of legislators demand higherefficiencies from traditional internal combustion engine ICE vehicles.Therefore, more and more vehicles are equipped with efficiencyincreasing measures, such as charging apparatuses and emission reductiondevices. Well known are, for instance, charging apparatuses wherein acompressor may be driven by an e-motor (e-charger) and/or an exhaust gaspowered turbine (turbocharger).

Common compressors thereby comprise a compressor housing and acompressor wheel which is arranged in the housing. In operation, air issucked through a compressor inlet of the housing to get accelerated andcompressed by the compressor wheel and then exits the compressor via avolute of the compressor housing. Each compressor has its characterizingcompressor map defining its operating range. This operating range ismainly bound by the surge line and the choke line in the compressor map.

To further improve the efficiency of the ICE, it is well known toenhance the compressor map, e.g. by preventing surging, i.e. by takingmeasures to move the surge line to the left. This can be done, forexample, by compressor inlet adjustment mechanisms. Common adjustmentmechanisms are configured, for instance, to increase the speed of theair flow, to modify the flow angle or to establish a flow pathrecirculation. When it comes to increasing the speed of the air flow, itis known to reduce an inlet diameter of the compressor inlet by means oforifice elements which are moved by an actuation ring. The actuationring itself is usually coupled to and moved by a plurality ofintermediate elements, such as a lever assembly, to, i.e. by anactuator. These measures and elements typically require space, mayincrease the weight, may lead to increased manufacturing costs and mayincrease the need for maintenance due to wear.

Accordingly, the objective of the present invention is to provide animproved compressor inlet adjustment mechanism.

SUMMARY

The present invention relates to an adjustment mechanism as set out inclaim 1. Furthermore, the present invention relates to a correspondingadjusting assembly, a compressor and a corresponding charging apparatuseach including such an adjustment mechanism as set out in claims 5, 14and 15, respectively. Other embodiments are described in the dependentclaims.

The inventive adjustment mechanism for variably adjusting thecross-section of a compressor inlet comprises a plurality of rotatableorifice elements and a transmission ring. Each orifice element has aplate body, a coupling element and a bearing pin. The transmission ringis mechanically coupled to the plurality of orifice elements via thecoupling elements. One of the orifice elements is configured as a driveorifice element. The bearing pin of the drive orifice element isconfigured as an elongated bearing pin. The elongated bearing pin isconfigured longer than the bearing pins of the other orifice elements.Furthermore, the elongated bearing pin is adapted to be coupled to anactuation system such that when the drive orifice element is moved bythe actuation system, movement is transmitted from the drive orificeelement via the transmission ring to the other orifice elements. Theinventive configuration of the adjustment mechanism results in adifferent force flow in comparison to known adjustment mechanisms. Theactuation force is led from an actuation system directly into the driveorifice element via rotation of the elongated bearing pin. Thereby thedrive orifice element together with its coupling element can be pivoted.The coupling element of the drive orifice element in turn interacts withthe transmission ring such that the transmission ring is rotated. Viathe transmission ring force is transmitted from the drive orificeelement to the other orifice elements thereby causing pivoting movementof the orifice elements to adjust the cross-section of a compressorinlet. The orifice elements are circumferentially distributed along thetransmission ring. Optionally, the orifice elements may be configuredand arranged such that they can contact respective adjacent orificeelements in a circumferential direction. Thereby, for instance the driveorifice element can push adjacent orifice elements during movementadditionally to the force transmission through the transmission ring.The orifice elements being adjacent to the drive orifice element can inturn push respective adjacent orifice elements. Thereby a progression ofdirect force transmission from one orifice element to another orificeelement can be accomplished. This auxiliary direct force transmissionfrom the drive orifice element to its adjacent orifice elements (andfurther on) can improve the dynamics of the adjustment mechanism,particularly it can support the initial movement of the transmissionring. The inventive configuration of the drive orifice element caneliminate the need for a lever assembly or other intermediate parts asused in known systems. Consequently, this leads to less required parts,reduced space requirements, a better packaging and decreasedmanufacturing costs.

In one aspect of the adjustment mechanism, the bearing pin is arrangedfurther radially outside on the respective orifice element than thecoupling element. In particular, the bearing pin is arranged furtherradially outside on the plate body than the coupling element.Additionally or alternatively the coupling element is arranged in aradial middle portion of the respective orifice element. Additionally oralternatively the bearing pin is arranged in a radial outer portion ofthe respective orifice element. In particular, the bearing pin isarranged at a radial outer end of the respective orifice element. Byarranging the bearing pin radially outside of the coupling element, thetraveling distance of the respective coupling element relative to thetransmission ring can be reduced. Thereby the potential wear of eachcoupling element and wear of the transmission ring can be reduced.Especially, an increasing distance between the coupling element and therespective bearing pin of one orifice element leads to a reducedrelative movement between each coupling element and the transmissionring. Furthermore, by arranging the bearing pin radially outside thecoupling element, i.e. farther away from the compressor axis in a radialoutside direction, less rotation of the whole orifice element isrequired for moving the plate body between an opened and a closedposition. This also results in less wear.

In another aspect, which is combinable with the previous aspect, thecoupling element and the bearing pin may protrude directly from theplate body of the respective orifice element in an axial direction. Inother words, the coupling element and the bearing pin are integrallyformed with the plate body.

In another aspect, which is combinable with any one of the previousaspects, each orifice element may have an upstream surface and adownstream surface. The upstream surface points in a first axialdirection to an upstream side. The downstream surface points in a secondaxial direction to a downstream side opposite the first axial direction.

In another aspect, which is combinable with the previous aspect, thecoupling elements may extend from the upstream surface in the firstaxial direction. Alternatively, the coupling elements may extend fromthe downstream surface in the second axial direction.

Additionally or alternatively to the previous aspect, the transmissionring may be arranged axially adjacent the upstream surfaces or axiallyadjacent the downstream surfaces.

Additionally or alternatively to the previous aspect, the couplingelements and the transmission ring may be arranged on the same of one ofthe upstream side or the downstream side.

Additionally or alternatively to the previous aspect, the elongatedbearing pin may always arranged on the upstream side. The elongatedbearing pin may extend from the upstream surface in the first axialdirection.

Additionally or alternatively to the previous aspect, the bearing pinsof the other orifice elements may extend from the upstream surface inthe first axial direction. Alternatively the bearing pins of the otherorifice elements extend from the downstream surface in the second axialdirection.

In another aspect, which is combinable with any one of the previousaspects, the transmission ring may have a plurality of circumferentiallyarranged recesses. Each coupling element may be operatively coupled toone respective recess. Additionally each recess may have a longitudinalshape extending in a substantially radial direction. Thereby, eachcoupling element can slide within the respective recess in a radialdirection. Furthermore, movement between the transmission ring and theorifice elements can be transmitted in a circumferential direction.

In another aspect, which is combinable with any one of the previousaspects, the adjustment mechanism may further comprise a housingportion. Additionally, the housing portion may have a bore.Additionally, the elongated bearing pin may extend through the bore tobe coupled to the actuation system outside the housing portion.Additionally, the housing portion may be an inlet port of a compressordefining the compressor inlet.

The present invention further relates to an adjustment assembly forvariably adjusting the cross-section of a compressor inlet. Theadjustment assembly comprises an adjustment mechanism of any one of theprevious aspects. Furthermore, the adjustment assembly comprises anactuation system. The actuation system is configured to actuate thedrive orifice element. That means the drive orifice element isoperatively coupled to the actuation system. The actuation system maycomprise a drive unit. The drive unit is configured as a rotatory driveunit. Additionally, a first geared structure may be arranged in a firstend portion of the elongated bearing pin. Additionally, the adjustmentassembly may further comprise a first geared element. The first gearedelement may be arranged at the first end portion and may comprise thefirst geared structure. The first geared element may be attached in arotationally fixed manner to the first end portion. The first gearedstructure may be arranged on a radial surface of the elongated bearingpin or on a radial surface of the geared element, i.e. a surfacepointing in a radial direction with respect to the elongated bearingpin. In embodiments comprising the first geared element, a length of thegeared element in a radial direction with respect to the elongatedbearing pin may be configured to place the actuation system closer orfurther away from the elongated bearing pin. In other words, byproviding the first geared element a distance between the actuationsystem and the elongated bearing pin and/or the housing portion can beadjusted. This enables a flexible placement of the actuation system byadequately configuring the first geared element. Furthermore, thepossibility is provided to use different actuation systems, for instanceactuation systems of different sizes. In other words, the first gearedstructure can either be provided directly in the elongated bearing pinor in an additional element, i.e. the first geared element. If the firstgeared structure is directly formed on the elongated bearing pin, thefirst geared structure may optionally be arranged in a geared recess ofthe elongated bearing pin. The geared recess may be formed in an endface of the elongated bearing pin. Thereby the actuation system candirectly be coupled to the elongated bearing pin in a very compactfashion. The actuation system can be arranged closer to the housingportion. Consequently, a more compact device can be provided.

In another aspect of the adjustment assembly, the first geared structuremay extend at least along an arc length of a circular sector.Additionally, the circular sector may be defined by a central angle θ₁between 5° to 360°, preferably between 10° to 60° and in particularbetween 15° and 45°. By adapting the central angle θ₁ smaller than 360°no full rotation is required. Furthermore, the manufacturing costs canbe reduced as a smaller area needs to be provided in a gearedconfiguration.

Additionally or alternatively to the previous aspect, the adjustmentassembly may further comprise a second geared structure. The secondgeared structure may be formed complementary to the first gearedstructure and may be operatively coupled to the drive unit. Furthermore,the second geared structure may be engagingly coupled to the firstgeared structure in order to rotate the elongated bearing pin. In otherwords, the actuation system may comprise the second geared structure.Additionally, the adjustment assembly may further comprise a rotatabledrive shaft. The rotatable drive shaft may be operatively coupled to thedrive unit. That means the actuation system may comprise the rotatabledrive shaft. Additionally, the second geared structure may directly beformed on the rotatable drive shaft. In particular, the second gearedstructure may directly be formed in a second shaft end portion of therotatable drive shaft. If the second geared structure is directly formedon the rotatable drive shaft, the second geared structure may optionallybe arranged in a geared recess of the rotatable drive shaft. The gearedrecess may be formed in a shaft end face of the rotatable drive shaft.Thereby the actuation system can directly be coupled to the elongatedbearing pin in a very compact fashion. The actuation system can bearranged closer to the housing portion. Consequently, a more compactdevice can be provided. Alternatively to being directly formed on therotatable drive shaft, the adjustment assembly, i.e. the actuationsystem may further comprise a second geared element which comprises thesecond geared structure. The second geared element may operatively becoupled to the drive unit. The second geared element may be arranged onthe rotatable drive shaft. In particular, the second geared element maybe arranged in a second shaft end portion of the rotatable drive shaft.Thereby the second geared element can be operatively coupled to thedrive unit via the rotatable drive shaft. Additionally, the secondgeared element may be attached to the rotatable drive shaft in arotationally fixed manner

In another aspect of the adjustment assembly which is combinable withthe previous aspect, the second geared structure may extend at leastalong an arc length of a circular sector. Additionally, the circularsector may be defined by a central angle θ₂ between 5° to 360°,preferably between 10° to 60° and in particular between 15° and 45°.

Alternatively to the previous aspect, the second geared element isconfigured as a gear rack.

The present invention further relates to a compressor of a chargingapparatus. The compressor comprises a compressor housing, an impellerand an adjustment assembly of any one of the previous aspects. Thecompressor housing defines a compressor inlet and a compressor outlet.The impeller is rotatably mounted in the compressor housing between thecompressor inlet and the compressor outlet. Additionally, if theadjustment mechanism comprises a housing portion, the housing portion ispart of the compressor housing. Furthermore, the housing portion formsthe compressor inlet. In other words, the housing portion serves asinlet port of the compressor. Thereby, the housing portion may beattached to the compressor housing. The housing portion may be arrangedupstream of the impeller.

The present invention further relates charging apparatus. The chargingapparatus comprises a compressor drive unit and a compressor of any oneof the previous aspects. The compressor is rotationally coupled to thecompressor drive unit via a shaft.

In one aspect of the charging apparatus, the compressor drive unit maycomprise a turbine. Additionally or alternatively the compressor driveunit may comprise an electric motor.

DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a sectional view of charging apparatus without theinventive adjustment mechanism;

FIGS. 2A-2B show the inventive adjustment mechanism in isometric viewsfrom the top (upstream side) and bottom (downstream side);

FIGS. 3A-3B show the adjustment mechanism of FIG. 2A in an opened and ina closed state;

FIG. 4A shows the adjustment mechanism including a housing portion, i.e.the adjustment assembly including an actuation system in an explodedview;

FIG. 4B shows the adjustment mechanism and the adjustment assembly ofFIG. 4A in an assembled state, the actuation system of the adjustmentassembly not being coupled to the elongated bearing pin;

FIGS. 5A-5B show the adjustment assembly in isometric sectional viewsfrom the top (upstream side) and bottom (downstream side);

FIG. 6 shows the compressor including the adjustment assembly of FIG. 4Ain an exploded view without an impeller;

FIG. 7 shows a sectional side view of the compressor of FIG. 6, but inassembled state;

FIG. 8 shows an isometric view of the compressor of FIG. 7, but with afirst geared element and a second geared element;

FIGS. 9A-9C show different configurations of the first geared structure;

FIGS. 10A-10D show different configurations of the second gearedstructure.

DETAILED DESCRIPTION

In the context of this invention, the expressions axially, axial oraxial direction is meant to be a direction parallel of or along an axis,i.e. rotational axis, of the transmission ring. When the adjustmentmechanism is mounted in a compressor housing, the axial direction alsosubstantially coincides with an axis of the compressor, i.e. with arotation axis of the compressor wheel. Thus, with reference to thefigures, see, especially FIG. 2A and FIG. 6, an axial dimension isdescribed with reference sign 22, a radial dimension extending“radially” away from the axial dimension 22 is described with referencesign 24. Furthermore, a circumferential dimension around the axialdimension 22 is described with reference sign 26. If an axial, radial orcircumferential directions/dimension is to be understood in another waythan just described it is explicitly indicated (e.g. radially from anaxis of the elongated bearing pin).

FIG. 1 schematically illustrates the inventive charging apparatus 400having a compressor 300 and a compressor drive unit 410. The compressor300 is rotationally coupled to the compressor drive unit 410 via a shaft420. In the exemplary embodiment of FIG. 1 the compressor drive unit 410is configured as an exhaust gas turbine. However, in alternativeembodiments the compressor drive unit 410 can be configured as anelectric motor or may be configured as a combination of an exhaust gasturbine and an electric motor. The compressor 300 comprises a compressorhousing 310 and an impeller 320. The compressor housing 310 defines acompressor inlet 312 and a compressor outlet 314. The impeller 320 isrotatably mounted in the compressor housing 310 between the compressorinlet 312 and the compressor outlet 314. Furthermore, the compressor 300comprises an adjustment assembly 30. The adjustment assembly 30comprises an adjustment mechanism 10 and an actuation system 230.

With reference to FIGS. 2A and 2B the adjustment mechanism 10 forvariably adjusting the cross-section 312 a of a compressor inlet 312will be explained in further detail. The adjustment mechanism 10comprises a plurality of rotatable orifice elements 100, 100′ and atransmission ring 210. Each orifice element 100, 100′ has a plate body130, a coupling element 110 and a bearing pin 120, 120′. Thetransmission ring 210 is mechanically coupled to the plurality oforifice elements 100, 100′ via the coupling elements 110 (see inparticular FIG. 2B). One of the orifice elements 100, 100′ is configuredas a drive orifice element 100′. The bearing pin 120′ of the driveorifice element 100′ is configured as an elongated bearing pin 120′. Theelongated bearing pin 120′ is configured longer than the bearing pins120 of the other orifice elements 100. Furthermore, the elongatedbearing pin 120′ is adapted to be coupled to an actuation system 230(not depicted here, see adjustment assembly 30, e.g., FIG. 4B or 5A)such that when the drive orifice element 100′ is moved by the actuationsystem 230, movement is transmitted from the drive orifice element 100′via the transmission ring 210 to the other orifice elements 100. Thus,for instance the length of the elongated bearing pin 120′ is adaptedlong enough to be coupled to the actuation system 230. Other adaptationsof the elongated bearing pin 120′ will be described later with referenceto the adjustment assembly 30. The inventive configuration of theadjustment mechanism 10 results in a different force flow in comparisonto known adjustment mechanisms. The actuation force is led from anactuation system 230 directly into the drive orifice element 100′ viarotation of the elongated bearing pin 120′. Thereby the drive orificeelement 100′ together with its coupling element 110 can be pivoted. Indetail the drive orifice element 100′ can be pivoted around the axis ofthe elongated bearing pin 120′. The coupling element 110 of the driveorifice element 100′ in turn interacts with the transmission ring 210such that the transmission ring 210 is rotated. Via the transmissionring 210 force is transmitted from the drive orifice element 100′ to theother orifice elements 100 thereby causing pivoting movement of theorifice elements 100 (around the respective axis of their respectivebearing pin 120) to adjust the cross-section 312 a of the compressorinlet 312. Thus, the adjustment mechanism 10 can be moved between anopened position or opened state in which the cross-section 312 a of thecompressor inlet 312 is maximal and a closed position or closed state inwhich the cross-section 312 a of the compressor inlet 312 is reduced.This is illustrated in FIGS. 3A and 3B. FIG. 3A shows the opened stateof the adjustment mechanism 10 in which the orifice elements 100, 100′are pivoted radially outside, i.e. radially away from the center (seearrow indicating the axial direction 22) of the transmission ring 210.In contrast hereto, FIG. 3A shows the closed state of the adjustmentmechanism 10 in which the orifice elements 100, 100′ are pivotedradially inside, i.e. radially towards from the center of thetransmission ring 210. In this closed state, the orifice elements 100,100′, i.e. their respective plate bodies 130 can block a radial outerportion of the cross-section 312 a of the compressor inlet 312 andthereby reduce the cross-section 312 a. To better understand the latterexplanations, reference is also given to FIG. 7 which more clearlydepicts this functionality as it shows the adjustment mechanism 10mounted in a compressor housing 310. Here it becomes evident, that whenthe adjustment mechanism 10 is depicted in a closed state, the orificeelements 100, 100′ block a portion of the compressor inlet 312 andthereby reduce the cross-section 312 a of the compressor inlet 312.

Again with reference to FIGS. 3A and 3B, it can be seen that the orificeelements 100, 100′ are distributed along the transmission ring 210 in acircumferential direction 26. The orifice elements 100, 100′ areconfigured and arranged such that they contact respective adjacentorifice elements 100, 100′ in a circumferential direction 26. Thephysical contact enables the possibility that the drive orifice element100′ can push adjacent orifice elements 100 during movement. This“direct push movement” can be exerted on adjacent orifice elements 100additionally to the force transmission through the transmission ring210. Those orifice elements 100 being adjacent to the drive orificeelement 100′ can in turn push respective adjacent orifice elements 100.Thereby a progression of direct force transmission from one orificeelement 100, 100′ to another orifice element 100, 100′ can beaccomplished. This auxiliary direct force transmission from the driveorifice element 100′ to its adjacent orifice elements 100 (and furtheron) can improve the dynamics of the adjustment mechanism 10. Inparticular, it can support the initial movement of the transmission ring210. The inventive configuration of the drive orifice element 100′ whichis directly coupleable with the actuation system 230 can eliminate theneed for a lever assembly or other intermediate parts as used in knownsystems. Consequently, this leads to less required parts, reduced spacerequirements, a better packaging and decreased manufacturing costs.

With further reference to FIGS. 2B and 3B, each orifice element 100,100′, more specifically each plate body 130, comprises a radial middleportion 136, a radial outer portion 138 and a radial outer end 138 a.The radial middle portion 136 is a portion of the plate body 130 whichis located in a radial middle area of the plate body 130 when theadjustment mechanism 10 is in the closed state. The radial outer portion138 is a portion of the plate body 130 which is located in a radialouter area of the plate body 130 when the adjustment mechanism 10 is inthe closed state. The radial outer end 138 a is a portion of the platebody 130 which is located in a radial outer end of the plate body 130when the adjustment mechanism 10 is in the closed state. When theadjustment mechanism 10 is moved to the opened state, the respectiveportions 138, 138 and the end 138 a correspondingly move too but remainfixed with respect to the respective plate body 130. Each respectivebearing pin 120, 120′ is arranged at the radial outer end 138 a of therespective orifice element 100, 100′ (see, e.g., FIG. 3B). Eachrespective coupling element 110 is arranged in the radial middle portion136 of the respective orifice element 100, 100′ (see, e.g., FIG. 2B).Alternatively, the bearing pin 120, 120′ can also be arranged in aradial outer portion 138 of the respective orifice element 100, 100 andneed not be arranged exactly at the radial outer end 138 a. However, inall embodiments the bearing pin 120, 120′ is preferentially arrangedfurther radially outside on the respective orifice element 100, 100′than the coupling element 110. By arranging the bearing pin 120, 120′radially outside of the coupling element 110, the traveling distance ofthe respective coupling element 110 relative to the transmission ring210 can be reduced. Thereby the potential wear of each coupling element110 and potential wear of the transmission ring 210 can be reduced.Especially, an increasing distance between the coupling element 110 andthe respective bearing pin 120, 120′ of a respective orifice element100, 100′ leads to a reduced relative movement between each couplingelement 110 and the transmission ring 210. Furthermore, by arranging thebearing pin 120, 120′ radially outside the coupling element 110, i.e.farther away from the compressor axis in a radial outside direction 24,less rotation of the whole orifice element 100, 100′ is required formoving the plate body 130 between an opened closed and a closedposition. This also results in less wear, in particular less wear of thebearing pin 120, 120′.

As depicted in FIGS. 2A and 2B each orifice element 100, 100′ has anupstream surface 132 and a downstream surface 134. More specifically,each plate body 130 of the respective orifice element 100, 100′ has anupstream surface 132 and a downstream surface 134. The upstream surface132 points in a first axial direction 22 a to an upstream side 132 a ofthe adjustment mechanism 10. The downstream surface 134 points in asecond axial direction 22 b to a downstream side 134 a of the adjustmentmechanism 10 opposite the first axial direction 22 a. Thus, the firstaxial direction 22 a extends opposite the second axial direction 22 b.In general, the upstream side 132 a and the downstream side 134 a aredefined by means of the flow direction of fluids through the compressorin the assembled state of the adjustment mechanism in a compressor 300during operation. Therefore, see additionally FIG. 7 which shows theadjustment mechanism 10 assembled in a compressor housing 310 clarifyingthe upstream side 132 a and downstream side 134 a also with respect tothe adjustment mechanism 10.

The coupling element 110 and the bearing pin 120, 120′ directly protrudefrom the plate body 130 of the respective orifice element 100, 100′generally in an axial direction 22. In the illustrated embodiments thebearing elements 120, 120′ extend in the first axial direction 22 a fromthe plate body 130 of the respective orifice element 100, 100′. In otherwords, the coupling element 110 and the bearing pin 120, 120′ areintegrally formed with the respective plate body 130 of one orificeelement 100, 100′. The coupling elements 110 extend in the second axialdirection 22 b from the plate body 130 of the respective orifice element100, 100′. The transmission ring 210 is arranged axially adjacent thedownstream surfaces 134 of the orifice elements 100, 100′. In otherwords, the transmission ring 210 is arranged axially adjacent thedownstream surfaces 134 of the plate bodies 130. The transmission ring210 has a plurality of circumferentially arranged recesses 212 (seeFIGS. 2B and 3B). Each coupling element 110 is operatively coupled toone respective recess 212. Each recess 212 has a longitudinal shapeextending in a substantially radial direction 22. Thereby, each couplingelement 110 can slide within the respective recess 212 in a radialdirection 22. Thus, the coupling elements 110 engage with a respectiverecess 212. That means the transmission ring 210 needs to be arranged onthe same side of the plate body 130 as the coupling elements 110.Thereby movement can be transmitted between the transmission ring 210and the orifice elements 100, 100′ in a circumferential direction 26.Alternatively, to extending from the downstream surface 134 in thesecond axial direction 22 b, the coupling elements 110 may extend fromthe upstream surface 132 in the first axial direction 22 a (notdepicted). In this case the transmission ring 210 may also be arrangedaxially adjacent the upstream surface 132 of the plate bodies 130.Preferably, the transmission ring 210 and the coupling elements 110 arearranged axially adjacent the downstream side 134 as this may lead to agood stability of the adjustment mechanism 10 during movement. Arrangingthe transmission ring 210 and the coupling elements 110 on the upstreamside 132 a may lead to a more compact device. The elongated bearing pin120′ must always be arranged on the upstream side 132 a. In other words,the elongated bearing pin 120′ must always extend from the upstreamsurface 132 in the first axial direction 22 a. Thereby an easyaccessibility to the actuation system 230 can be achieved. However, inalternative embodiments, some or all of the bearing pins 120 of theother orifice elements 100 can extend from the downstream surface 134 inthe second axial direction 22 b. In embodiments where some or all of thebearing pins 120, 120′ are arranged on the same side of the plate body130 as the transmission ring 210, the respective bearing pins need to bearranged radially outside the transmission ring 210. Bearing pins 120,120′ which are arranged on an opposite site of the plate body 130 thanthe transmission ring 210 do not necessarily be arranged radiallyoutside the transmission ring 210.

As depicted in FIGS. 4A and 4B, the adjustment mechanism 10 furthercomprises a housing portion 220 with an inlet portion 226 and a flangeportion 228. The housing portion 220 may serve as an inlet port for thecompressor 300 and defines the compressor inlet 312. The housing portion220 comprises a bore 222 which is configured to receive the elongatedbearing pin 120′. The bore 222 extends through the flange portion 228 inthe axial direction 22. Described in other words, the elongated bearingpin 120′ extends through the bore 222 to be coupled to the actuationsystem 230 outside the housing portion 220. Optionally, a bushing (notdepicted) may be arranged in the bore 222 and may rotatably support theelongated bearing pin 120′. FIGS. 5B and 7 show that the housing portion220 further comprises a plurality of circumferentially distributedbearing bores 224. The bearing bores 224 receive the bearing pins 120.Alternatively, if the bearing pins 120 are oriented in the oppositedirection, i.e. if the bearing pins 120 extend from the body plates 130in the second axial direction 22 b, no bearing bores 224 may be providedin the housing portion 220. Instead, respective bearing bores 224 may bedirectly provided in the compressor housing 310. Alternatively, anadditional bearing ring (not depicted) with a plurality ofcircumferentially distributed bearing bores 224 may be provided betweenthe compressor housing 310 and the orifice elements 100, 100′ or betweenthe housing portion 220 and the orifice elements 100, 100′ to supportthe bearing pins 120 of the orifice elements 100.

The present invention further relates to an adjustment assembly 30 forvariably adjusting the cross-section 312 a of a compressor inlet 312(see FIG. 4A). The adjustment assembly 30 comprises the adjustmentmechanism 10 with the housing portion 220. Additionally, the adjustmentassembly 30 comprises an actuation system 230, which is schematicallydepicted in FIGS. 4A to 5B. The actuation system 230 is configured toactuate the drive orifice element 100′. That means the drive orificeelement 100′ is operatively coupled to the actuation system 230. Theactuation system 230 comprises a drive unit 234 which is also merelyschematically depicted. The drive unit 234 is configured as a rotatorydrive unit. That means it generates a rotatory drive movement. This canhelp to further reduce the space requirements of the adjustment assembly30. In some alternative embodiments, the drive unit 234 may beconfigured as a translational drive unit, i.e. generating atranslational drive movement. This can be the case, for instance wherethe actuation system 230 comprises a gear rack which will be explainedfurther below. For illustrative purposes, the actuation system 230 isdepicted distanced from and not coupled to the drive orifice element100′ in FIGS. 4A and 4B. Thereby the function of the drive orificeelement 100′ becomes more clear. Especially, in FIG. 4B it can be seenthat the elongated bearing pin 120′ extends through the housing portion220. However, it is to be understood that in the assembled state, theactuation system 230 is coupled, i.e. physically coupled, to the driveorifice element 100′ (see FIGS. 5A and 5B). Here in FIGS. 5A and 5B, theactuation system 230 is directly coupled to the elongated bearing pin120′. Therefore, the actuation system 230 is arranged on the elongatedbearing pin 120′. Described in other words, the elongated bearing pin120′ extends into the actuation system 230. In this exemplaryembodiment, the actuation system 230 is arranged directly at housingportion 220. This configuration results in an extremely compactassembly. For illustrative purposes, merely the flange portion 228 ofthe housing portion 220 is depicted in these figures, although thehousing portion 220 also comprises the inlet portion 226 as explainedfurther above. With further reference to FIGS. 5A and 5B, the adjustmentassembly can additionally comprise a sealing 250 which is arrangedbetween the housing portion 220 and the elongated bearing pin 120′. Thissealing 250 can, for instance, be configured as a sealing ring. In theembodiment of FIGS. 5A and 5B, the actuation system 230 is mounted tothe housing portion 220. The sealing 250 is arranged between theactuation system 230 and the housing portion 220. In alternativeembodiments, the actuation system 230 need not be mounted directly atthe housing portion 220. In particular, in such cases the sealing 250may be arranged between the housing portion 220 and the elongatedbearing pin 120′ as described above. For instance, the sealing 250 canbe arranged in or at the bore 222.

With reference to FIGS. 9A to 9C, the elongated bearing pin 120′comprises a first geared structure 142. The first geared structure 142can either be provided directly in the elongated bearing pin 120′ (seeFIGS. 9A and 9B) or in an additional element, i.e. a first gearedelement 140 (see FIG. 9C).

When the first geared structure 142 is provided directly in theelongated bearing pin 120′, it is arranged in a first end portion 122′of the elongated bearing pin 120′. The first geared structure 142 may beconfigured as an external toothing (see FIG. 9A) or an internal toothing(see FIG. 9B). The first geared structure 142 is arranged on a radialsurface of the elongated bearing pin 120′. That means the first gearedstructure 142 is arranged on a surface of the elongated bearing pin 120′pointing in radial direction with respect to the rotation axis of theelongated bearing pin 120′. When the first geared structure 142 isconfigured as an external toothing, the first geared structure 142 isarranged on a radial outer surface of the elongated bearing pin 120′. Inother words, the first geared structure 142 is arranged on a surface ofthe elongated bearing pin 120′ pointing in radial outward direction ofthe rotation axis of the elongated bearing pin 120′. When the firstgeared structure 142 is configured as an internal toothing, the firstgeared structure 142 is arranged on a radial inner surface of theelongated bearing pin 120′. In other words, the first geared structure142 is arranged on a surface of the elongated bearing pin 120′ pointingin radial inward direction of the rotation axis of the elongated bearingpin 120′. Therefore, the elongated bearing pin 120′ may comprise ageared recess 146. The geared recess 146 is formed in an end face 122 a′of the elongated bearing pin 120′. The first geared structure 142 isarranged in the geared recess 146. By providing the first gearedstructure 142 directly in the elongated bearing pin 120′, the actuationsystem 230 can directly be coupled to the elongated bearing pin 120′ ina very compact fashion. The actuation system 230 can be arranged closerto the housing portion 220 (see, e.g., FIGS. 5A and 5B). Consequently, amore compact device can be provided.

FIG. 9C shows the adjustment assembly 30 comprising the first gearedelement 140. The first geared element 140 is arranged at the first endportion 122′ and comprises the first geared structure 142. The firstgeared element 140 is attached in a rotationally fixed manner to theelongated bearing pin 120′. Preferably, the first geared element 140 isattached in a rotationally fixed manner to the first end portion 122′.The first geared structure 142 is arranged on a radial surface of thefirst geared element 140, i.e. a surface pointing in a radial directionwith respect to the rotation axis of the elongated bearing pin 120′. Alength of the first geared element 140 in a radial direction withrespect to the rotation axis of the elongated bearing pin 120′ may beconfigured to place the actuation system 230 closer or further away fromthe elongated bearing pin 120′. In other words, by providing the firstgeared element 140 a distance between the actuation system 230 and theelongated bearing pin 120′ and/or the housing portion 220 can beadjusted. This enables a flexible placement of the actuation system 230by adequately configuring the first geared element 140. Furthermore, thepossibility is provided to use different actuation systems 230, forinstance actuation systems 230 of different sizes.

With reference to FIGS. 9A and 9C, the first geared structure 142extends only along an arc length 144 a of a circular sector 144. Thecircular sector 144 is defined by a central angle θ₁ which is preferablybetween 10° to 60°. Alternatively, the central angle θ₁ may liesomewhere between 5° to 360° and in particular between 15° and 45°.Thus, in some embodiments the first geared structure 142 mayalternatively also extend along the full circumference of the elongatedbearing pin 120′ or the first geared element 140. The first gearedelement 140 may be substantially shaped in a circular sector 144 or maysubstantially comprise only the circular sector 144 (see FIG. 9C).Alternatively, the first geared element 140 may be shaped circular (notdepicted). By adapting the central angle θ₁ smaller than 360° no fullrotation is required. Furthermore, the manufacturing costs can bereduced as a smaller area needs to be provided in a gearedconfiguration.

With reference to FIGS. 10A to 10D, the adjustment assembly 30 comprisesa second geared structure 242. More specifically, the actuation system230 comprises the second geared structure 242. The second gearedstructure 242 is engagingly coupled to the first geared structure 142 inorder to rotate the elongated bearing pin 120′. To achieve this, thesecond geared structure 242 is formed complementary to the first gearedstructure 142. Furthermore, the second geared structure 242 isoperatively coupled to the drive unit 234. As depicted in FIGS. 10A to10 C, the adjustment assembly 30 further comprises a rotatable driveshaft 232. More specifically, the actuation system 230 comprises therotatably drive shaft 232. The rotatable drive shaft 232 is operativelycoupled to the drive unit 234. The second geared structure 242 mayeither be provided directly in the rotatable drive shaft 232 (see FIG.10A) or in an additional element, i.e. a second geared element 240 (seeFIGS. 10B and 10C). The rotatable drive shaft 232 has a first shaft endportion 233 and a second shaft end portion 235. The first shaft endportion 233 is coupled to the drive unit 230. The second shaft endportion 235 is coupled to the elongated bearing pin 120′. Morespecifically, if the second geared element 240 is provided, the secondshaft end portion 235 is coupled to the elongated bearing pin 120′ viathe second geared element 240.

When the second geared structure 242 is provided directly in therotatable drive shaft 232, it is arranged in the second shaft endportion 235 of the rotatable drive shaft 232. That means, the secondgeared structure 242 is directly formed on the rotatable drive shaft 232(see FIG. 10A). In the example of FIG. 10A, the second geared structure242 is configured as an internal toothing. Alternatively, the secondgeared structure 242 may be configured as an external toothing (onlydepicted together with an additional element in FIG. 10C, butanalogously to FIG. 9A). The second geared structure 242 is arranged ona radial surface of the rotatable drive shaft 232. That means the secondgeared structure 242 is arranged on a surface of the rotatable driveshaft 232 pointing in radial direction with respect to the rotation axisof the rotatable drive shaft 232. When the second geared structure 242is configured as an external toothing, the second geared structure 242is arranged on a radial outer surface of the rotatable drive shaft 232.In other words, the second geared structure 242 is arranged on a surfaceof the rotatable drive shaft 232 pointing in radial outward direction ofthe rotation axis of the rotatable drive shaft 232. When the secondgeared structure 242 is configured as an internal toothing, the secondgeared structure 242 is arranged on a radial inner surface of therotatable drive shaft 232. In other words, the second geared structure242 is arranged on a surface of the rotatable drive shaft 232 pointingin radial inward direction of the rotation axis of the rotatable driveshaft 232. Therefore, the rotatable drive shaft 232 comprises a gearedrecess 246. The geared recess 246 is formed in a shaft end face 235 a ofthe rotatable drive shaft 232. The second geared structure 242 isarranged in the geared recess 246. By providing the second gearedstructure 242 directly in the rotatable drive shaft 232, the actuationsystem 230 can directly be coupled to the elongated bearing pin 120′ ina very compact fashion. The actuation system 230 can be arranged closerto the housing portion 220 (see, e.g., FIGS. 5A and 5B). Consequently, amore compact device can be provided.

Also when having a second geared element 240, the second gearedstructure 242 may be configured as an external toothing (see FIG. 10C)or an internal toothing (see FIG. 10B). The second geared element 240comprises the second geared structure 242. The second geared element 240is arranged in the second shaft end portion 235 of the rotatable driveshaft 232. The second geared element 240 is attached in a rotationallyfixed manner to the rotatable drive shaft 232. Preferably, the secondgeared element 240 is attached in a rotationally fixed manner to thesecond shaft end portion 235. The second geared element 240 isoperatively coupled to the drive unit 234. More specifically, the secondgeared element 240 is operatively coupled to the drive unit via therotatable drive shaft 232. The second geared structure 242 is arrangedon a radial surface of the second geared element 240, i.e. a surfacepointing in a radial direction with respect to the rotation axis of therotatable drive shaft 232. A length of the second geared element 240 ina radial direction with respect to the rotation axis of the rotatabledrive shaft 232 may be configured to place the actuation system 230closer or further away from the elongated bearing pin 120′. In otherwords, by providing the second geared element 240 a distance between theactuation system 230 and the elongated bearing pin 120′ and/or thehousing portion 220 can be adjusted. This enables a flexible placementof the actuation system 230 by adequately configuring the second gearedelement 240. Furthermore, the possibility is provided to use differentactuation systems 230, for instance actuation systems 230 of differentsizes.

In general, various combinations of the first geared structure 142and/or the first geared element 140 and the second geared structure 242and/or the second geared element 240 are possible. For instance, thefirst geared structure 142 according to the embodiment of FIG. 9A may becombined with the second geared structure 242 according to any of theembodiments depicted in FIG. 10A, 10B, 10C or 10D. The embodiment ofFIG. 10D thereby represents a variation wherein the second gearedelement 240 is configured as a gear rack. In this case, the actuationsystem 230 does not comprise a rotatable drive shaft 232. Instead, thegear rack is directly coupled with the drive unit 234 and the drive unitis configured as a translational drive unit 234.

Analogously to the first geared structure 142, the second gearedstructure may extend only along an arc length 244 a of a circular sector244 (see FIG. 10C). The circular sector 244 is defined by a centralangle θ₂ which is preferably between 10° to 60°. Alternatively, thecentral angle θ₂ may lie somewhere between 5° to 360° and in particularbetween 15° and 45°. Thus, in some embodiments the second gearedstructure 242 may alternatively also extend along the full circumferenceof the rotatable drive shaft 232 (if the second geared structure 242 isdirectly provided on the rotatable drive shaft 232 and configured as anexternal toothing) or the second geared element 240. The second gearedelement 240 may be substantially shaped in a circular sector 244 or maysubstantially comprise only the circular sector 244 (see FIG. 10C).Alternatively, the second geared element 240 may be shaped circular (notdepicted). By adapting the central angle θ₁ smaller than 360° no fullrotation is required. Furthermore, the manufacturing costs can bereduced as a smaller area needs to be provided in a gearedconfiguration.

With reference to FIGS. 6, 7 and 8, the compressor 300 is shown in moredetail. As already stated further above, the compressor 300 comprisesthe adjustment assembly 30 including the adjustment mechanism 10 withthe housing portion 220. Furthermore, the compressor 300 comprises thecompressor housing 310. The adjustment assembly 30 is inserted into thecompressor housing 310 (see FIG. 8). Thus, the housing portion 220 formspart of the compressor housing 310. More specifically, the housingportion 220 forms the compressor inlet 312. In other words, the housingportion 220 serves as inlet port of the compressor 300. The housingportion 220 is attached to the compressor housing 310 via its flangeportion 228. Although the impeller 320 is not depicted FIGS. 6, 7 and 8,the housing portion 220 is arranged upstream of the impeller 320 (see,e.g., FIG. 1). FIG. 7 shows in detail how the orifice elements 100, 100′and the transmission ring 210 is arranged in the compressor housing 310.It is clearly visible that the elongated bearing pin 120′extends throughthe housing portion 222 to be coupled with the actuation system 230,i.e. the drive unit 234 outside the compressor housing 310. Here in FIG.7, the elongated bearing pin 120′ is directly coupled to the actuationsystem 230. FIG. 8 shows another exemplary configuration in which theelongated bearing pin 120′ is coupled to the actuation system 230 viathe first geared element 140 and the second geared element 240.

It should be understood that the present invention can also(alternatively) be defined in accordance with the following embodiments:

-   -   1. An adjustment mechanism (10) for variably adjusting the        cross-section 312 a of a compressor inlet (312) comprising:        -   a plurality of rotatable orifice elements (100, 100′) each            having a plate body (130), a coupling element (110) and a            bearing pin (120, 120′); and        -   a transmission ring (210) mechanically coupled to the            plurality of orifice elements (100) via the coupling            elements (110);        -   wherein        -   one of the orifice elements (100, 100′) is configured as a            drive orifice element (100′) whose bearing pin (120′) is            configured as an elongated bearing pin (120′) being longer            than the bearing pins (120) of the other orifice elements            (100), wherein the elongated bearing pin (120′) is adapted            to be coupled with an actuation system (230),        -   such that when the drive orifice element (100′) is moved by            the actuation system (230), movement is transmitted from the            drive orifice element (100′) via the transmission ring (210)            to the other orifice elements (100).    -   2. The adjustment mechanism (10) of embodiment 1, wherein the        bearing pin (120, 120′) is arranged further radially outside on        the respective orifice element (100, 100′), in particular on the        plate body (130) than the coupling element (110).    -   3. The adjustment mechanism (10) of any one of the previous        embodiments, wherein the coupling element (110) and the bearing        pin (120, 120′) protrude directly from the plate body (130) of        the respective orifice element (100, 100′) in an axial direction        (22).    -   4. The adjustment mechanism (10) of any one of the previous        embodiments, wherein the coupling element (110) is arranged in a        radial middle portion (136) of the respective orifice element        (100, 100′) wherein the bearing pin (120, 120′) is arranged in a        radial outer portion (138), in particular at an radial outer end        (138 a) of the respective orifice element (100, 100′).    -   5. The adjustment mechanism (10) of any one of the previous        embodiments, wherein each orifice element (100, 100′) has an        upstream surface (132) and a downstream surface (134), wherein        the upstream surface (132) points in a first axial direction (22        a) to an upstream side (132 a) and wherein the downstream        surface (134) points in a second axial direction (22 b) to a        downstream side (134 a) opposite the first axial direction (22        a).    -   6. The adjustment mechanism (10) of embodiment 5, wherein the        coupling elements (110) extend from the upstream surface (132)        in the first axial direction (22 a) or from the downstream        surface (134) in the second axial direction (22 b).    -   7. The adjustment mechanism (10) of any one of embodiments 5 or        6, wherein the transmission ring (210) is arranged axially        adjacent the upstream surfaces (132) or axially adjacent the        downstream surfaces (134).    -   8. The adjustment mechanism (10) of any one of embodiments 5 to        7, wherein the coupling elements (110) and the transmission ring        (210) are arranged on the same of one of the upstream side (132        a) or the downstream side (134 a).    -   9. The adjustment mechanism (10) of any one of embodiments 5 to        8, wherein the elongated bearing pin (120′) is always arranged        on the upstream side (132 a) and extends from the upstream        surface (132) in the first axial direction (22 a).    -   10. The adjustment mechanism (10) of any one of embodiments 5 to        9, wherein the bearing pins (120) of the other orifice elements        (100) extend from the upstream surface (132) in the first axial        direction (22 a) or from the downstream surface (134) in the        second axial direction (22 b).    -   11. The adjustment mechanism (10) of any one of the previous        embodiments, wherein the transmission ring (210) has a plurality        of circumferentially arranged recesses (212), wherein each        coupling element (110) is operatively coupled with one        respective recess (212).    -   12. The adjustment mechanism (10) of embodiment 5, each recess        (212) has a longitudinal shape extending in a substantially        radial direction (24) such that each coupling element (110) can        slide within the respective recess (212) in a radial direction        (22) and such that movement between the transmission ring (210)        and the orifice elements (100, 100′) can be transmitted in a        circumferential direction (26).    -   13. The adjustment mechanism (10) of any one of the previous        embodiments, further comprising a housing portion (220),        optionally having a bore (222), and optionally, wherein the        elongated bearing pin (120′) extends through the bore (222) to        be coupled with the actuation system (230) outside the housing        portion (220).    -   14. The adjustment mechanism (10) of embodiment 13, wherein the        housing portion (220) is an inlet port of a compressor (300)        defining the compressor inlet (312).    -   15. An adjustment assembly (30) for variably adjusting the        cross-section 312 a of a compressor inlet (312), comprising:        -   an adjustment mechanism (10) of any one of the previous            embodiments; and        -   an actuation system (230) to actuate the drive orifice            element (100′), wherein the actuation system (230) is            coupled to the elongated bearing pin (120′) and, optionally,            wherein the actuation system (230) comprises a drive unit            (234), in particular, wherein the drive unit (234) is            rotatory.    -   16. The adjustment assembly (30) of embodiment 15, wherein a        first geared structure (142) is arranged in a first end portion        (122′) of the elongated bearing pin (120′).    -   17. The adjustment assembly (30) of embodiment 16, further        comprising a first geared element (140) arranged at the first        end portion (122′) and comprising the first geared structure        (142).    -   18. The adjustment assembly (30) of embodiment 16, wherein the        first geared structure (142) is directly formed on the elongated        bearing pin (120′), and optionally, wherein a geared recess        (146) is formed in an end face (122 a′) of the elongated bearing        pin (120′) and, wherein the geared recess (146) comprises the        first geared structure (142).    -   19. The adjustment assembly (30) of any one of embodiments 16 to        18, wherein the first geared structure (142) extends at least        along an arc length (144 a) of a circular sector (144), and        optionally, wherein the circular sector (144) is defined by a        central angle θ₁ between 5° to 360°, preferably between 10° to        60° and in particular between 15° and 45°.    -   20. The adjustment assembly (30) of any of embodiments 16 to 19,        further comprising a second geared structure (242) which is        formed complementary to the first geared structure (142) and        which is operatively coupled with the drive unit (234), wherein        the second geared structure (242) is engagingly coupled with the        first geared structure (142) in order to rotate the elongated        bearing pin (120′).    -   21. The adjustment assembly (30) of embodiment 20, further        comprising a rotatable drive shaft (232) being operatively        coupled with the drive unit (234).    -   22. The adjustment assembly (30) of embodiment 21, wherein the        second geared structure (242) is directly formed on the        rotatable drive shaft (232), in particular in a second shaft end        portion (235) of the rotatable drive shaft (232), and        optionally, wherein a geared recess (246) is formed in a shaft        end face (235 a) of the rotatable drive shaft (232) and, wherein        the geared recess (246) comprises the second geared structure        (242).    -   23. The adjustment assembly (30) of any one of embodiments 20 or        21, further comprising a second geared element (240) operatively        coupled with the drive unit (234) and comprising the second        geared structure (242).    -   24. The adjustment assembly (30) of embodiment 23, if dependent        on embodiment 21, wherein second geared element (240) is        arranged on the rotatable drive shaft (232), in particular in a        second shaft end portion (235) of the rotatable drive shaft        (232) in order to be operatively coupled with the drive unit        (234) via the rotatable drive shaft (232).    -   25. The adjustment assembly (30) of any one of embodiments 20 to        24, wherein the second geared structure (242) extends at least        along an arc length (244 a) of a circular sector (244), and        optionally, wherein the circular sector (244) is defined by a        central angle θ₂ between 5° to 360°, preferably between 10° to        60° and in particular between 15° and 45°.    -   26. The adjustment assembly (30) of any one of embodiments 23 or        24, wherein second geared element (240) is configured as a gear        rack.    -   27. The adjustment assembly (30) of any one of embodiments 15 or        16, 18 to 22 wherein the actuation system (230) is directly        coupled with the elongated bearing pin (120′) of the drive        orifice element (100′).    -   28. A compressor (300) of a charging apparatus (400), the        compressor comprising:        -   a compressor housing (310) having a compressor inlet (312)            and a compressor outlet (314);        -   an impeller (320) rotatably mounted in the compressor            housing (310) between the compressor inlet (312) and the            compressor outlet (314); and        -   an adjustment assembly (30) of any one of the previous            embodiments.    -   29. The compressor (300) of embodiment 28, if dependent on        embodiment 13, wherein the compressor housing (310) comprises        the housing portion (220), and wherein the housing portion (220)        forms the compressor inlet (312).    -   30. A charging apparatus (400) comprising:        -   a compressor drive unit (410); and        -   a compressor (300) of any one of the previous embodiments            which is rotationally coupled to the compressor drive unit            (410) via a shaft (420).    -   31. The charging apparatus (400) of embodiment 30, wherein the        compressor drive unit (410) comprises a turbine and/or an        electric motor.

1. An adjustment mechanism (10) for variably adjusting the cross-section(312 a) of a compressor inlet (312), the adjustment mechanism (10)comprising: a plurality of rotatable orifice elements (100, 100′) eachhaving a plate body (130), a coupling element (110) and a bearing pin(120, 120′); and a transmission ring (210) mechanically coupled to theplurality of orifice elements (100) via the coupling elements (110);wherein one of the orifice elements (100, 100′) is configured as a driveorifice element (100′) whose bearing pin (120′) is configured as anelongated bearing pin (120′) being longer than the bearing pins (120) ofthe other orifice elements (100), wherein the elongated bearing pin(120′) is adapted to be coupled with an actuation system (230), suchthat when the drive orifice element (100′) is moved by the actuationsystem (230), movement is transmitted from the drive orifice element(100′) via the transmission ring (210) to the other orifice elements(100).
 2. The adjustment mechanism (10) of claim 1, wherein the couplingelement (110) is arranged in a radial middle portion (136) of therespective orifice element (100, 100′), and wherein the bearing pin(120, 120′) is arranged in a radial outer portion (138) of therespective orifice element (100, 100′).
 3. The adjustment mechanism (10)of claim 1, wherein each orifice element (100, 100′) has an upstreamsurface (132) and a downstream surface (134), wherein the upstreamsurface (132) points in a first axial direction (22 a) to an upstreamside (132 a) and wherein the downstream surface (134) points in a secondaxial direction (22 b) to a downstream side (134 a) opposite the firstaxial direction (22 a).
 4. The adjustment mechanism (10) of claim 1,further comprising a housing portion (220) having a bore (222), whereinthe elongated bearing pin (120′) extends through the bore (222) to becoupled with the actuation system (230) outside the housing portion(220).
 5. An adjustment assembly (30) for variably adjusting thecross-section (312 a) of a compressor inlet (312), the adjustmentassembly (30) comprising: the adjustment mechanism (10) of claim 1; andan actuation system (230) to actuate the drive orifice element (100′),wherein the actuation system (230) is coupled to the elongated bearingpin (120′).
 6. The adjustment assembly (30) of claim 5, furthercomprising a first geared structure (142) arranged in a first endportion (122′) of the elongated bearing pin (120′).
 7. The adjustmentassembly (30) of claim 6, further comprising a first geared element(140) arranged at the first end portion (122′) and comprising the firstgeared structure (142).
 8. The adjustment assembly (30) of claim 6,wherein the first geared structure (142) is directly formed on theelongated bearing pin (120′).
 9. The adjustment assembly (30) of claim6, wherein the first geared structure (142) extends at least along anarc length (144 a) of a circular sector (144).
 10. The adjustmentassembly (30) of claim 6, further comprising a second geared structure(242) which is formed complementary to the first geared structure (142)and which is operatively coupled with the drive unit (234), wherein thesecond geared structure (242) is engagingly coupled with the firstgeared structure (142) in order to rotate the elongated bearing pin(120′).
 11. The adjustment assembly (30) of claim 10, wherein the secondgeared structure (242) is directly formed on the rotatable drive shaft(232).
 12. The adjustment assembly (30) of claim 10, further comprisinga second geared element (240) operatively coupled with the drive unit(234) and comprising the second geared structure (242).
 13. Theadjustment assembly (30) of claim 5, wherein the actuation system (230)is directly coupled with the elongated bearing pin (120′) of the driveorifice element (100′).
 14. A compressor (300) of a charging apparatus(400), the compressor (300) comprising: a compressor housing (310)having a compressor inlet (312) and a compressor outlet (314); animpeller (320) rotatably mounted in the compressor housing (310) betweenthe compressor inlet (312) and the compressor outlet (314); and theadjustment assembly (30) of claim
 5. 15. A charging apparatus (400)comprising: a compressor drive unit (410); and the compressor (300) ofclaim 14 which is rotationally coupled to the compressor drive unit(410) via a shaft (420).
 16. The adjustment mechanism (10) of claim 3,wherein the elongated bearing pin (120′) is always arranged on theupstream side (132 a) and extends from the upstream surface (132) in thefirst axial direction (22 a).
 17. The adjustment assembly (30) of claim5, wherein the actuation system (230) comprises a drive unit (234) thatis rotatory.
 18. The adjustment assembly (30) of claim 8, wherein ageared recess (146) is formed in an end face (122 a′) of the elongatedbearing pin (120′), and wherein the geared recess (146) comprises thefirst geared structure (142).
 19. The adjustment assembly (30) of claim9, wherein the circular sector (144) is defined by a central angle θ₁between 5° to 360°.
 20. The adjustment assembly (30) of claim 11,wherein a geared recess (246) is formed in a shaft end face (235 a) ofthe rotatable drive shaft (232), and wherein the geared recess (246)comprises the second geared structure (242).